Folded Product Made From Extruded Profile and Method of Making Same

ABSTRACT

A product made from an extruded sheet or web of material having a non-linear cross-section, and the process of making the product is provided. The extruded web or extrudate is plastically deformed in selected areas and then folded. When folded into the appropriate shape, the extrudate is formed into a product having a plurality of cells. Optionally, the cells can include one or more openings, allowing access to an interior of the cell and reducing the weight of the product.

FIELD OF THE INVENTION

This invention relates generally to a product for structural, packaging,and other applications and the process of making the product.

BACKGROUND OF THE INVENTION

In the aerospace industry, honeycomb products have been used as a corecomponent for sandwich panels and boards that are resistant to bucklingand bending. These honeycomb products each comprise a plurality ofcells, which in cross-section have a generally hexagonal shape. Suchproducts may be fabricated from aluminum, fiber paper or plastic, amongother materials. A sandwich structure may be prepared having two coverlayers or skins which are welded, adhesively bonded or otherwise securedto the honeycomb product to create a multi-layered or multi-laminatematerial. Interest expressed in other industrial sectors concerning theuse of light weight sandwich structures is continually growing, due atleast in part to the realization of its high strength properties whilemaintaining a relatively low structural weight per volume of product.

A multi-layered or multi-laminate material having a honeycomb product asthe core thereof may be used in the packaging industry. However, inautomobile part packaging and comparable markets, such a product mustcompete with corrugated paperboard or corrugated plastic or likematerials which may be produced quickly and relatively inexpensively.

U.S. Pat. No. 6,183,836 discloses a honeycomb core for use in a sandwichmaterial in which the material of the honeycomb core is cut and thenfolded to create a plurality of hexagonal cells. Due to the cuts in thesheet prior to folding the sheet, the resultant cells may be weaker thandesired.

A process for producing a folded honeycomb core for use in sandwichmaterials from a continuous uncut web is disclosed in U.S. Pat. No.6,726,974. U.S. Pat. No. 6,800,351 discloses another process forproducing a folded honeycomb core which includes scoring a corrugatedmaterial before rotating interconnected corrugated strips. The honeycombcore resulting from using either of these methods may have materialwhich adds to the weight of the honeycomb core but may not significantlyimprove the strength of the honeycomb core.

Accordingly, there is a need for a product which may be used alone or ina multi-layered material, and which has a favorable strength to weightratio.

There is further a need for a process for manufacturing a product suchas a honeycomb product for use alone or in a multi-layered materialwhich is less expensive and may be produced in higher quantities thanheretofore known processes.

SUMMARY OF THE INVENTION

These and other objectives of the invention have been attained in aprocess for producing a product such as a honeycomb product for usealone or in a sandwich-like product. The process includes extruding aweb of material which has a non-planar profile, i.e. has a non-linearcross-section, plastically deforming or treating portions of such web,and then folding the treated web to produce the product. Otherfabrication operations may optionally be included in the process. Theprocess of preparing a web of material suitable for further fabricationinto a product is rendered efficient in part by producing an extrudatehaving a non-linear cross-section. For purposes of this document, linearshall be defined as a single straight continuous line, the shortestdistance between two points. Each of the extrudates or extruded websillustrated herein has a non-planar profile and has a non-linearcross-section. Shapes of other webs of material not shown are intendedto be included in such a definition.

The extrudate displays a non-linear cross-sectional configuration uponexiting the extruder head. This cross-section may assume any of avariety of shapes. A relatively simple shape would be that of acontinuous sine wave. Another example is corrugated plastic. Morecomplex shapes can include interrupted sine wave sections connected bystraight lines, one or more polygons connected by straight lines, nestedpolygons, and the like, as needed or desired in connection withultimately preparing the core structure of interest.

Representative product like a honeycomb product can be produced using avariety of starting materials capable of being processed through anextruder, including various plastic compositions, in an efficient mannerto produce a product having good strength to weight properties. Theproduct may be used alone, or may be incorporated as a part of amulti-layered sandwich-like material to produce, for example, panels orsheets used in structural applications. More broadly, the products ofthe present invention may be used in any desired environment orindustry. For example, product may be produced under conditions whichgenerate a material having a high surface area. The material may then befurther treated to produce a product having surface activity, whichcould be used for example in catalytic applications.

According to one aspect of this invention, a process of making a productcomprises extruding a web of material having a predetermined or desiredwidth or transverse dimension, the extruded web having a generallynon-linear cross-section; plastically deforming such as flattening areasof the extruded web; and folding the web.

As defined herein, the term “web” encompasses material processed inextrusion equipment intended to accept the specific material introducedinto that equipment, and issuing or exiting from an extruder head. Theextrudate has a non-linear cross-section. In one aspect of the presentinvention, a plurality of openings may be introduced into the extrudedweb. These openings can be introduced by stamping the material, but mayalso include processing of the extruded web by one or more tools tothereby form the openings. As used herein, a tool is intended toencompass any device, or energy flowing from that device, which is usedto desirably alter the physical appearance of the web. Thus, by way ofexample and not by limitation, a tool for the purpose of forming aplurality of openings in the extruded web can include a laser cutter,one or more rotating cutting blades, a perforating or slitting machine,and the like.

The process of plastically deforming or flattening selected areas of theextruded web can comprise contacting the extruded web with an elementwhich may be heated. Alternatively, selected areas of the extruded webcan be flattened by a tool applying pressure, heat, or a combination ofpressure and heat, in one or more selected areas. The process offlattening may alternatively precede the introduction of openings intothe extruded web, may follow the introduction of openings into theextruded web, or the two processes may occur substantiallysimultaneously.

One type of non-linear cross-section shape which the extruded web maydisplay is a generally corrugated shape with flattened peaks andflattened valleys along the transverse dimension of the extruded web.Further, the extruded web is folded along transversely extending foldlines during the folding step. One or more individual cells can beformed as a result of the folding step, for example where a section ofthe extrudate is oriented at 90° from its original position by thefolding operation.

The process of making a product like a honeycomb product may alsoencompass extruding a web having a generally non-linear cross-sectionwhich in addition forms a plurality of substantially closed channels.Small openings in one or more channels, up to all channels in theextruded web, may be introduced to facilitate introduction of a coolingmedium to the extrudate, as required based on the particular materialutilized to produce the web and the complexity and wall thickness of theweb, or portions thereof. The openings may extend in a continuousfashion along the entire length of the channel, or openings may beintermittently introduced along the channel length. Further processingwith one or more tools can be effected on this type of extruded web in amanner similar to that discussed above to alter the appearance of theextruded web, by cutting, flattening, folding, and the like.

The product of this invention can also comprise an extruded web having anon-linear cross-section formed into a plurality of similar cellsarranged in rows, wherein at least some of the rows of cells are beingmade of two row walls, each of the row walls having alternating planarand non-planar regions, the planar regions of the adjacent row wallsbeing joined together and non-planar regions of the adjacent row wallsdefining side walls of the cells, wherein each of the cells have sidewalls, a top and a bottom. This product can be characterized by at leastone opening created by at least one tool in at least some of its cells.

In a further aspect, the product has at least some openings in lateralside walls of at least some of the cells. At least some of the cellopenings can be of a pre-defined size, or of a pre-defined shape, orboth a pre-defined size and shape.

The product made from extruded web material can be produced bymanipulating the web material into a plurality of similar cells arrangedin rows, at least some of those cells being made of a continuous cellwall, the continuous cell wall may have any desired shape including theshape generally of a ring, wherein the cells are oriented substantially90° to the longitudinal dimension of the extrusion web material.

Another aspect of the invention is a product such as a honeycomb productmade by the process of extruding a web of material having a transversedimension, the extruded web having a generally non-linear cross-section;creating a plurality of generally planar areas in the extruded web;folding the extruded web along edges of the generally planar areas tocreate a plurality of identical cells arranged in rows, at least some ofthe rows of cells being made of two row walls, each of the row wallshaving planar and non-planar regions, the regions of adjacent row wallsbeing joined together, and non-planar regions of adjacent row wallsdefining side walls of the cells, each of the cells also having a topand bottom. If desired, one may form in at least some of the cells anopening created by at least one tool.

The tops and bottoms of the cells of the honeycomb product describedherein may be in the shape of a polygon. More specifically, thehoneycomb product may be shaped such that the polygon is a hexagon. In afurther aspect of the invention, each of the cells may have an openingallowing access to an interior of the cell.

In another aspect of the invention, where a plurality of openings areformed in the web of material, those openings typically extendcompletely through the web. The openings may be circular, but may assumeone of any number of other shapes, such as oval, hourglass, asymmetric,and the like. The openings optionally correspond to locations along theweb wherein material has been removed to realize good strength to weightproperties.

Regardless of the method used to create the product, one advantage isthat a light weight, strong product may be quickly and easilymanufactured in a desired size or height. The product of this invention,which is produced according to the processes described herein, has agood strength to weight ratio even without forming openings in the web,and may be made from many different materials quickly and inexpensively.The strength to weight ratio may be improved by strategic removal ofmaterial from the extruded web at some time in the process offabricating the product. The product may be used alone, incorporatedinto a multi-layered sandwich-like material, or used in any otherdesired manner.

BRIEF DESCRIPTION OF THE DRAWINGS

The objectives and features of the present invention will become morereadily apparent when the following detailed description of the drawingsis taken in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of a web of material having a generallynon-planar cross-section being extruded from an extruder;

FIG. 1A is a perspective view of a web of material having a generallynon-linear cross-section being extruded from an extruder head ofalternate design;

FIG. 2 is a perspective view of a portion of the extruded web of FIG. 1;

FIG. 2A is a perspective view of a portion of the extruded web of FIG.1A;

FIG. 3 is a perspective view of a portion of the extruded web of FIG. 2being treated to create transversely extending flats;

FIG. 3A is a side elevational view of a portion of the extruded web ofFIG. 1A being treated to create transversely extending flats;

FIG. 4 is a perspective view of a portion of the plastically deformedweb of FIG. 3 being folded to create rows of cells;

FIG. 4A is a side elevational view of the web of FIG. 3A being folded tocreate re-oriented portions containing channels;

FIG. 5 is a perspective view of a portion of the plastically deformedweb of FIG. 3 being further folded to create a portion of a honeycombproduct;

FIG. 5A is a side elevational view of the web of FIG. 4A afterorientation to create a portion of a honeycomb product;

FIG. 6 is a perspective view of a row of cells;

FIG. 7 is a perspective view of a portion of the plastically deformedweb of FIG. 4 being treated to create a plurality of openings in theplastically deformed web;

FIG. 8 is a perspective view of a portion of the plastically deformedweb of FIG. 7 being further folded to create rows of cells;

FIG. 9 is a perspective view of an extruded web having been plasticallydeformed and punched simultaneously according to another aspect of thisinvention;

FIG. 10 is a perspective view of a portion of the plastically deformedweb of FIG. 9 being folded to create rows of cells;

FIG. 1B is a perspective view of a web of material having a generallynon-linear cross-section being extruded from an extruder head ofalternate design;

FIG. 2B is a perspective view of a portion of the extruded web ofmaterial extruded from the extruder head of FIG. 1B;

FIG. 3B is an end view of the extruded web of FIG. 2B;

FIG. 4B is a perspective view of a portion of the extruded web of FIG.2B being treated to create a plurality of plastically deformed areas orregions;

FIG. 5B is a perspective view of a portion of the plastically deformedweb of FIG. 4B being folded to create rows of cells;

FIG. 6B is a perspective view of a portion of the extruded web of FIGS.1B-5B being folded to create a portion of a product;

FIG. 7B is a perspective view of a portion of the extruded web of FIG.2B being treated to create a plurality of plastically deformed areas orregions in the form of flats;

FIG. 8B is a perspective view of a portion of the plastically deformedweb of FIG. 7B being folded to create rows of cells;

FIG. 1C is a perspective view of a web of material having a generallynon-linear cross-section being extruded from an extruder head ofalternate design;

FIG. 2C is a perspective view of a portion of the extruded web ofmaterial extruded from the extruder head of FIG. 1C; and

FIG. 3C is an end view of the extruded web of FIG. 2C.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring to FIG. 5, a portion of a honeycomb product 10 according toone embodiment of this invention is shown. The honeycomb product 10 maybe made using numerous processes including those described herein andothers within the scope of the claims. FIG. 5 shows a portion of ahoneycomb product 10 comprising a plurality of rows 12 of identicalcells 14 made from extruded web or sheet of material. FIG. 6 illustratesone such row 12 of cells 14. Referring to FIG. 5, the honeycomb product10 has a generally planar upper surface 16 in a generally horizontalplane P1 and a generally planar lower surface 18 in a generallyhorizontal plane P2, the distance between which defines the height H ofthe honeycomb product 10. The height H of the honeycomb product 10 maybe any desired distance and is not intended to be limited to the heightof the illustrated portion of the honeycomb product.

As shown in FIGS. 4 and 5, each row 12 of cells 14 is made by bringingtwo adjacent hinged row walls 20 together in an accordion-like manner.Each row wall 20 has alternating planar and non-planar regions or areas22, 24, respectively. Each non-planar region 24 in FIGS. 4 and 5comprises three rectangular walls comprising a half-hexagon incross-section. Regions 24 are bounded by planar regions 22. During theprocess of making the honeycomb product 10, adjacent row walls 20 arebrought together so that the planar regions 22 of adjacent row walls 20at least partially contact each other and the non-planar regions 24 ofrow walls 20 define sides or side walls 74, 76 of cells 14.

In certain applications, such as for example when a web of thermoplasticmaterial is heated at some stage in the manufacture of the honeycombproduct 10, the planar regions 22 of adjacent row walls 20 may bebonded, welded or secured to each other without any additional material.Alternatively, adhesive or other bonding agent may be used to secureadjacent row walls 20 together to complete the rows 12 of cells 14. Thenon-planar regions 24 of adjacent row walls 20 are spaced apart anddefine the shape or configuration of the cells 14 after themanufacturing process has been completed. Outermost portions or sides 74of adjacent cells 14 in different rows 12 may contact each other and maybe secured to each other in certain applications of this invention.

Although the drawings illustrate each non-planar region 24 of each rowwall 20 having a cross-sectional configuration of a half-hexagon, thenon-planar regions of the row walls may have any desired cross-sectionalconfiguration, such as for example a curved or arcuate or sinuouscross-sectional configuration. The creation of the side walls or sides74,76 of the cells 14 is described in more detail below. Depending uponthe application, the cells 14 may be any desired shape or size.

As best illustrated in FIG. 6, each cell 14 has a top 28 and a bottom 30of a predetermined size and/or shape. As shown in FIG. 5, the tops 28 ofthe cells 14 are located in plane P1 and make up part of the uppersurface 16 of the honeycomb product 10. Likewise, the bottoms 30 of thecells 14 are located in plane P2 and make up part of the lower surface18 of the honeycomb product 10. The top 28, bottom 30 and sides 72, 74of the cell 14 define a cell interior 32.

In the illustrated embodiment, each cell top 28 and bottom 30 is apolygon and more particularly a hexagon. However, if the non-planarregions of the row walls were in the shape of half a cylinder then thetops and bottoms of the cells would be circular or oval and the cellswould have a cylindrical interior.

FIGS. 1-4 illustrate a method or process of making a honeycomb product10 which may be used alone, in a multi-layered material or product, orin any desired manner. FIG. 1 illustrates an extruder 40 extruding a webof material 42 which is shown in more detail in FIG. 2. Although oneconfiguration of extruder 40 and extruder head 41 is illustrated, anytype or configuration of extruder known in the art may be used. Theextruder and extruder head configurations will vary as a function of thematerial being extruded and the cross-section of the extrudate. Thematerial can include any of a variety of plastic compositions and anyother material capable of being extruded, and can encompass additionalcompositions which can be further processed to produce a honeycombproduct.

In FIG. 2, the extruded web 42 travels in a direction indicated by arrow43 and has a pair of opposed side edges 45, the linear distance betweenwhich defines the width or transverse dimension of the extruded web 42.The extruded web 42 may be any desired material of any desired thicknessand/or width.

The extruded web 42 has a generally non-linear cross-section orcross-sectional configuration. In cross-section, the extruded web 42 hasa generally corrugated configuration or shape including a plurality offlattened peaks 48 and a plurality of flattened valleys 50 joinedtogether by connecting portions 52. Each of the flattened peaks 48,flattened valleys 50 and connecting portions 52 are longitudinallyextending as shown in FIG. 2. The flattened valleys 50 are all generallyco-planar in a horizontal plane P3. Likewise, the flattened peaks 48 areall generally co-planar in a horizontal plane P4 above the plane P3. Thelinear distance between the planes P3 and P4 defines the height H1 ofthe corrugations 46. Although one shape or configuration of extruded web42 is illustrated in FIG. 2, the extruded web 42 may assume numerousother non-linear configurations in cross-section. For example, theexpanded view of the extruder head in FIG. 1A shows an alternatecross-sectional shape which can be used to create the non-linearcross-section extruded web. A perspective view of the extruded web 42′formed by the alternate extruder head design is provided in FIG. 2A.

FIGS. 3 and 4 illustrate a step in this process of making honeycombproduct 10 comprising plastically deforming or flattening at leastselected portions or areas 54, 56 of the extruded web 42 to create aplastically deformed extruded web 58. This plastic deformation mayinclude using movable tools 60, 61 such as shown in FIG. 3 to interruptthe continuous corrugations 46 formed in the emerging extruded web 42and create a plurality of corrugated regions or areas 62 each comprisinga plurality of corrugations 46 extending in a first direction generallyparallel the direction of travel 43 of the extruded web 42 orlongitudinally, and a plurality of flats or flattened areas 54, 56 eachextending in a second direction perpendicular to the first direction,transversely or from side-to-side. The size of these regions or areas62, 54 and 56 may vary depending upon the desired size or shape of thecells 14 of the honeycomb product 10.

Although tool 60 is illustrated as comprising three bars 64 joinedtogether with connectors 66 (only one being shown for clarity) and tool61 is illustrated as comprising two bars 64 joined together withconnectors 65 (only one being shown for clarity), respectively, thesetools 60, 61 may comprise any number of bars of any desired size orconfiguration joined together or not. Although two tools areillustrated, any number of tools of any desired type or configurationmay be used. Again, the term tool is not intended to be limiting and mayinclude any tool known in the art.

During the step of plastically deforming at least selected portions ofthe extruded web 42, the bars 64 of the tools 60, 61 may be chilled, atambient temperature, or heated by any desired method to facilitateprocessing. Such heating is illustrated schematically by arrows 38. Thisheating step is optional and may be used in certain applications only.In other applications it may be omitted partially or entirely. Althoughit is shown schematically after the flats 54, 56 have been created inthe extruded web 42, this heating step may occur any time during thismanufacturing process.

Due to the creation of the flattened areas or flats 54, 56, eachcorrugation 46 may have an end portion 69 which extends between a peak48 and a valley 50. These end portions 69 are illustrated as each beingin the shape of a trapezoid but may be other shapes, depending upon theshape of the corrugations.

As best illustrated in FIGS. 3 and 4, each generally rectangular,transversely extending flat or flattened area 56 is located in the planeP3 of the extruded web 42. Each generally rectangular, transverselyextending flat or flattened area 54 is located in plane P4 above theplane P3 of the extruded web 42 and coplanar with the plane of theflattened peaks 48 of corrugations 46. Flattened areas 56 and 54alternate between corrugated regions 62. As seen in FIG. 4, due to theshape of the tools 60, 61, each flat or flattened area 54 has side walls70 extending from the outer edges of the flat 54 to the flattenedvalleys 50 in the corrugated regions 62. These side walls 70 areillustrated as each being in the shape of a trapezoid but may be othershapes, depending upon the shape of the corrugations. Although notshown, the corrugations may have a semi-circular, sinuous, curved orother cross sectional configuration.

As shown in FIG. 4, the plastically deformed web portion 58 is thenfolded along transversely extending fold lines 72 located generally onthe edges of the flats 54, 56. Such fold lines 72 may be optionallyscored or perforated at any step in the manufacturing process with cuts71 to assist folding. Such scoring may be made by a separate tool ortools. As shown in FIG. 5, after the plastically deformed web portion 58is folded along transversely extending fold lines 72, side walls 70 layunderneath and may contact the raised flat 54, and end walls 69 ofcorrugations 46 rest on and contact flats 56.

As best illustrated in FIG. 6, side walls 70 abut and are underneathportions of the raised flats 54. These two ply areas compriseapproximately half of the tops 28 of some of the cells 14. In such cellsthe bottom 30 of the cell 14 is a single ply which was formed in theflat 56 before folding. As shown in FIG. 6, end walls 69 abut and areabove portions of the flats 56 to form approximately half of the bottoms30 of other cells 14. In such cells the top 28 of the cell 14 is asingle ply which was formed in the flat 54 prior to folding. Thus, inone row 12 of cells 14, each cell 14 has a single ply top 28 and adouble ply bottom 30. In adjacent rows of cells 14, each cell 14 has adouble ply top 28 and a single ply bottom 30.

As shown in FIGS. 4, 5 and 6, after the plastically deformed web portion58 is folded along transversely extending fold lines 72, thecorrugations 46 or non-planar regions 24 of the row walls 20 become theside walls 74,76 of the cells 14. More particularly, the generallyplanar peaks 48 of corrugations 46 shown in FIG. 4 become the outmostside walls 74 of the cells 14 and the generally planar connectingportions 52 of corrugations 46 become additional side walls 76 of thecells 14. As shown in FIGS. 5 and 6, within a row 12 of cells 14, theplanar portions 22 of row walls 20 come together to create flattenedtwo-ply portions 77 of row 12. Side walls 74, 76 along with the top 28and bottom 30 of each cell 14 define a cell interior 32.

The last step in the process is to cut the extruded web 42 at anydesired location. FIG. 4 illustrates a cutter 78 at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a honeycomb product 10 of a desired length.

FIGS. 7-8 illustrate another method or process of making a honeycombproduct which may be used alone or in a multi-layered material orproduct. FIG. 7 illustrates an extruded web 42 a traveling in adirection indicated by arrow 43 a and having a pair of opposed sideedges 45 a, the linear distance between which defines the width ortransverse dimension of the extruded web 42 a. The extruded web 42 a maybe any desired material of any desired thickness and/or width. Theextruded web 42 a is identical to extruded web 42 described above.

The extruded web 42 a is then treated as described above and illustratedin FIG. 3 to create a plastically deformed web portion 58 a having aplurality of corrugations 46 a. As seen in FIG. 7, the corrugations 46 amay comprise coplanar flattened peaks 54 a in a plane P6 and flattenedvalleys 56 a in the plane P5 of the extruded web 42 a with generallyrectangular flat connecting portions 52 a extending therebetween.Lastly, each corrugation 46 a may have an end portion 69 a. These endportions 69 a are illustrated as each being in the shape of a trapezoidbut may be other shapes, depending upon the shape of the corrugations.

As best illustrated in FIG. 7, each generally rectangular, transverselyextending flat or flattened area 56 a is located in the plane P5 of theextruded web 42 a. Therefore, each generally rectangular, transverselyextending flat or flattened area 54 a is located in plane P6 above theplane P5 of the extruded web 42 a and coplanar with the flattened peaks48 of corrugations 46 a. Flattened areas 56 a and 54 a alternate betweencorrugated areas 62 a. Each flat 54 a has side walls 70 a extending fromthe outer edges of the flat 54 a to the flattened valleys 50 a in thecorrugated regions 62 a. These side walls 70 a are illustrated as eachbeing in the shape of a trapezoid but may be other shapes, dependingupon the shape of the corrugations. Although not shown, the corrugationsmay have a semi-circular, sinuous, curved or other cross sectionalconfiguration.

FIG. 7 illustrates a movable tool 82 in the form of a punch press whichis used to remove material 84 from plastically deformed web 58 a inpredetermined or preselected locations. In FIG. 7, the punch press ortool 82 has a plurality of punchers 86 mounted on a plate 88 atpreselected or predetermined locations or positions to create aplurality of rectangular openings 34 a through predetermined orpreselected portions of the plastically deformed web 58 a. Theseopenings 34 a become the openings in the honeycomb product boa describedabove. See. FIG. 8. Although illustrated as being rectangular, theopenings 34 a may be of any predefined desired size or shape andstrategically located at any desired location on a portion of unrolledweb. For example, the holes or openings 34 a may be circular and beoriented such that each cell 14 has at least one opening 34 a allowingaccess to the interior of the cell 14.

Although a punch press is illustrated, any other tool, such as a lasercutter, may be used to create the openings 34 a through any portion ofthe plastically deformed portion 58 a of the extruded web 42 a tolighten the extruded web 42 a so that when this portion of the web 42 ais formed into a honeycomb product boa, the resultant honeycomb productboa has a relatively high strength-to-weight ratio due, at least inpart, to the removal of such material during the process ofmanufacturing the honeycomb product.

Although the tool 82 is illustrated beneath the extruded web 42 a, tool82 may be located above the extruded web 42 a or at any desiredlocation. More than one tool may be used if desired.

As shown in FIGS. 7-8, the strategic locations of the openings 34 a aresuch that the openings 34 a are located along the flats 54 a, 56 a ofthe plastically deformed web 58 a, along the flattened peaks 48 a of thecorrugations 46 a and along connecting portions 52 a of corrugations 46a. As shown in FIG. 7 each opening 34 a is illustrated as beinggenerally rectangular but may be any predefined or preselected shape orsize. As shown in FIGS. 7 and 8, some of the holes 34 a in flats 54 a,56 a extend through the bottoms 30 a and tops 28 a of cells 14 a.Likewise, holes 34 a through the connecting portions 52 a of thecorrugations 62 a extend through the side walls 76 a of cells 14 a.

As shown in FIG. 7, after the openings 34 a have been bored, punched orotherwise made, the plastically deformed web portion 58 a is then foldedalong transversely extending fold lines 72 a located generally on theedges of the flats 54 a, 56 a. As shown in FIGS. 7 and 8, after theplastically deformed web 58 a is folded along transversely extendingfold lines 72 a, side walls 70 a lay underneath the raised flats 54 aand end walls 69 a of corrugations 62 a rest on flats 56 a.

The last step in the process is to cut the extruded web 42 a at anydesired location. FIG. 7 illustrates a cutter 78 a at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a honeycomb product boa of a desired length.

FIG. 8 shows a portion of the resultant honeycomb product boa along withskins or layers 80 (shown in phantom) one or both of which may besecured to at least one of the upper and lower surfaces 16 a, 18 a ofhoneycomb product boa to create a multi-layered product for any desireduse. Such skins may be incorporated into a product having a honeycombcore or product made in accordance with any aspect of the presentinvention including via any method described or contemplated herein.

FIGS. 9-10 illustrate another method or process of making a honeycombproduct lob which may be used alone or in a multi-layered material orproduct.

FIGS. 9 and 10 illustrate another method or process of making ahoneycomb product lob which may be used alone or in a multi-layeredmaterial or product, comprising plastically deforming at least portionsof the extruded web 42 b. Plastic deformation may include using movabletools 60 b, 61 b such as shown in FIG. 9 to create a plurality ofcorrugated regions or areas 62 b comprising a plurality of corrugations46 b extending in a first direction generally parallel the direction oftravel 43 b of the web 42 b or longitudinally, and a plurality offlattened areas or regions 54 b, 56 b each extending in a seconddirection perpendicular to the first direction, transversely or fromside-to-side. The size of these regions or areas 62 b, 54 b and 56 b mayvary depending upon the desired size or shape of the cells 14 b of thehoneycomb product 10 b. See FIG. 10.

FIG. 9 illustrates movable tools 60 b, 61 b, which in addition toplastically deforming the extruded web 42 b also remove material 84 bfrom plastically deformed web 58 b in predetermined or preselectedlocations. In FIG. 9, each of the tools 60 b, 61 b has a plurality ofpunchers 86 b mounted on bars 64 b at preselected or predeterminedlocations or positions to create a plurality of circular openings 34 bthrough predetermined or preselected portions of the plasticallydeformed web 58 b. These openings 34 b become the openings in thehoneycomb product 10 b described above. Although illustrated ascircular, the openings 34 b may be of any desired shape andstrategically located at any desired location on a portion of theextruded web.

Although one configuration of tool 60 b (and 61 b) is illustratedcomprising bars 64 b joined by connectors 66 b (and 65 b), any otherconfiguration or type of tool may be used to plastically deform extrudedportions of web 42 b. Such tools may simultaneously create openings 34 bthrough any portion of the extruded web to lighten the extruded web 42 bso that when this portion of the web 42 b is folded to create honeycombproduct 10 b, the resultant honeycomb product 10 b has a relatively highstrength-to-weight ratio due, at least in part, to the removal of suchmaterial during the process of manufacturing the honeycomb product 10 b.

Although the tools 60 b and 61 b are illustrated respectively above andbelow extruded web 42 b, the orientation of tools 60 b and 61 b may bereversed, or at any other desired location, such as one after the otherin a staggered format. Any number of tools 60 b, 61 b may be used ifdesired.

During the step of plastically deforming at least selected portions ofthe extruded web 42 b, the bars 64 b of the tools 60 b, 61 b may bechilled, at ambient temperature, or heated by any desired method tofacilitate processing. Such heating is illustrated schematically byarrows 38 b. This heating step is optional and may be used in certainapplications only. In other applications it may be omitted partially orentirely. This heating step may occur any time during this manufacturingprocess.

As shown in FIG. 10, after the web 42 b has been plastically deformedand the openings 34 b have been created, the plastically deformed webportion 58 b is then folded along transversely extending fold lines 72 blocated generally on the edges of the flats 54 b, 56 b. As shown inFIGS. 9 and 10, after the plastically deformed web of material 58 b isfolded along transversely extending fold lines 72 b, side walls 70 b layunderneath the raised flats 54 b and end walls 62 b of corrugations 60 brest on flats 56 b.

The last step in the process is to cut the plastically deformed extrudedweb 58 b at any desired location. FIG. 10 illustrates a cutter 78 b atone location. However, one or more cutting tools or devices may be usedat any desired location to create a honeycomb product 10 b of a desiredlength.

As noted above, the cross-section of the extruded web can assume anynumber of shapes. FIGS. 1A-5A illustrate an alternative method ofproducing a honeycomb product, and the product made by that method.

The temperature needed to process a plasticated material through anextruder and out an extruder head, such as 41′ in FIG. 1A, inconjunction with the properties of the material being extruded, theextruder speed, and complexity of the desired cross-section shape, maycreate an extruded web 42′ which may retain an unacceptably highinternal heat after exiting the extruder head 41′. If not cooled to anacceptable temperature promptly after exiting the extruder head, such anextrudate may warp or show other indicia of degradation due to excessivelevels of heat being retained. As shown in FIG. 2A, the channels 44 ofthe web 42′, though open at one end, may be otherwise effectively closedto transport of air or other heat exchange medium. Such channels 44 aredescribed herein as being closed.

To improve access, one or more access openings 101 may be introducedinto one or more longitudinally extending channels 44 of the web 42′.Creation of an access opening 10 into a channel forms a modified channel44′ described herein as being substantially closed. See FIG. 2A. Theaccess opening 10 may be created in the web 42′ by appropriate machiningof the extruder head 41′, or by the action of a cutting ormaterial-removing tool (not shown) downstream of the extruder head 41′.Only one access opening 101 is shown in FIG. 2A on only one channel 44,but additional channels 44 can have one or more access openings 10, upto all of the channels in the extrudate. The access opening or openingscan vary in size or shape as needed to facilitate transport ofsufficient quantities of a heat exchange medium between the interior andexterior of a channel 44. The access opening 101 is depicted as beingcontinuous along the channel 44, but this is not required. Any number ofaccess openings 101 may be any desired length.

FIG. 1A depicts an alternate extrusion cross-section shape as shown inextruder head 41′. FIG. 2A depicts an alternate extruded web 42′ formedby use of extruder head 41′ containing closed corrugations, or channels44, the channel as depicted having a hexagonal shape in cross-section.

FIGS. 3A-5A depict side elevational views of the process of flatteningportions of an extruded web of the general configuration depicted inFIG. 2A having channels therein, followed by folding and re-orientingportions of the extruded web to create a honeycomb structure, portionsof the extruded web being re-oriented at 90° relative to their originalmachine direction orientation or position.

As shown in FIG. 3A, sections 110 of the extruded web 42′ may beflattened by tools 116, alternating the sections 110 being compressedinto upper flats 118 and lower flats 120. Tool 116 may apply pressureonly, heat only, or a combination of pressure and heat, to create flats118, 120.

Additional portions 124 a-d shown in FIG. 3A each contain at least onechannel disposed horizontally, which may be either closed orsubstantially closed. At least one portion is capable of beingmanipulated by a folding operation to mate with an adjacent portion,i.e., 124 a with 124 b, 124 b with 124 c, or 124C with 124 d, as shownin FIGS. 4A and 5A, to form vertically oriented cells 14′.

FIG. 4A depicts portions 124 a-d in varying degrees of re-orientation,from an original machine direction having closed channels disposedhorizontally, to an orientation at 90° relative to the original machinedirection, wherein the channels, now cells 14′, are substantiallyvertical. The portions 124 a-d re-orient along hinge lines 128.

FIG. 5A depicts the portions 124 a-d, along with similarly disposedportions, after folding and re-orientation. The resulting honeycombproduct 10′ is comprised in part of re-oriented portions 124 a, 124 b,124 c, and 124 d, with upper flats 118 and lower flats 120 respectivelydisposed above and below selected portions 124 a-124 d, the upper andlower flats being offset relative to each other.

FIG. 1B depicts an extruder 40″ with an alternate extruder head 41″ usedto extrude an extrusion 42″ having a non-planar profile and non-linearcross-section as shown in FIGS. 2B and 3B. FIG. 2B depicts a portion ofthe extruded web 42″ formed by use of extruder head 41″, the extrudedweb 42″ having a non-linear cross-section. For purposes of thisdocument, the portion of extruded web 42″ shown in FIG. 2B has anon-planar profile because it does not comprise a single solid flatsheet of material. The present invention is intended to cover allextrusions which are not solid flat sheets or webs of material.

As seen in FIG. 3B, the extruded web 42″ has spaced upper and lowerhorizontal walls 130 in planes P7 and P8, the linear distance betweenthese planes defining the height H2 of the extrudate 42″. The extrudate42″ also has side walls 132, the distance between which defines thewidth or transverse dimension W2 of the extrudate 42″. Lastly, theextrudate 42″ has a plurality of spacers 134 extending between thehorizontal walls 130 and spaced from each other so as to define aplurality of flutes or channels 136 which extend longitudinally or inthe direction of travel 43 of the web. As shown in FIG. 3B, these flutesor channels 136 have a rectangular shape in cross-section. As seen inFIG. 2B, the extruded web 42″ travels in a direction indicated by arrow43. The extruded web 42″ may be any desired material of any desiredthickness and/or width. This type of extrusion, if made of plastic isknown as one type of corrugated plastic.

One advantage of the present invention is the ability to extrude aproduct with reduced weight or density compared to the weight or densityof a single solid sheet or web of the same material of the samedimensions. Due to the presence of holes, flutes or channels 136 in theextrudate 42″, as best shown in FIG. 3B, the weight of any length ofextrudate 42″ is less than half the weight of a solid piece of materialof the same dimensions. The same is also true of the extrudate shown inFIG. 2.

FIGS. 4B and 5B illustrate additional steps in this process of makingproduct 10″. FIG. 4B illustrates the step of plastically deforming atleast selected portions or areas 138 of the extruded web 42″ to create aplastically deformed extruded web 58″. This plastic deformation mayinclude using movable tools 140, 142 such as shown in FIG. 4B tointerrupt the continuous corrugations or flutes 136 formed in theemerging extruded web 42″ and create a plurality of generally V-shapedplastically deformed regions or areas 138 each extending generallyperpendicular to the direction of travel 43 of the extruded web 42″ ortransversely or from side-to-side. The size of these regions or areas138 may vary depending upon numerous factors including the desired sizeor shape of the cells 14 of the resulting product 10″.

Although tool 140 is illustrated as comprising six deforming members 144joined together with connectors 146 (only one being shown for clarity)and tool 142 is illustrated as comprising five deforming members 148joined together with connectors 150 (only one being shown for clarity),respectively, these tools 140, 142 may comprise any number of deformingmembers of any desired size or configuration joined together or not.Although two movable tools are illustrated, any number of tools of anydesired type or configuration may be used. Again, the term tool is notintended to be limiting and may include any tool known in the art.

During the step of plastically deforming at least selected portions ofthe extruded web 42″, the deforming members 144, 148 of tools 140, 142,respectively, may be chilled, at ambient temperature, or heated by anydesired method to facilitate processing. Such heating is illustratedschematically by arrows 152. This heating step is optional and may beused in certain applications only. In other applications it may beomitted partially or entirely. Although it is shown schematically duringthe creation of the plastic deformed areas 138 of the extruded web 42″using tools 140, 142, this heating step may occur any time during thismanufacturing process.

As shown in FIGS. 5B and 6B, the plastically deformed web portion 58″ isthen folded along transversely extending fold lines 154 locatedgenerally in the planes P7 and P8 of the extrudate 42″. See FIG. 3B.Such fold lines 154 may be optionally scored or perforated at any stepin the manufacturing process with cuts (not shown) to assist folding.Such scoring may be made by a separate tool or tools. As shown in FIG.6B, after the plastically deformed web portion 58″ is folded alongtransversely extending fold lines 154, horizontal walls 130 of extrudate42″ become vertically orientated and the flutes 136 become thevertically oriented cells 14″ of the resultant product 10″

Another step in the process may be to cut the extruded web 42″ at anydesired location. FIG. 4B illustrates a cutter 78 at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a product 10″ of a desired length.

FIG. 6B shows a portion of the resultant product 10″ along with skins orlayers 80 (shown in phantom) one or both of which may be secured to atleast one of the upper and lower surfaces of product 10″ to create amulti-layered or sandwich-like product for any desired use. As shown inFIG. 6B, the plastically deformed web 58″ is folded alternatively inupper and lower planes P7 and P8 to create a plurality of blocks 137,each block 137 containing a row 139 of vertically oriented cells 14″. Ifdesired, adjacent blocks 137 may be adhesively or otherwise joined toeach other to create product 10″ with or without any skins 80.

FIGS. 7B and 8B illustrate another method or process of making a product160 which may be used alone or in a multi-layered material or product.FIG. 7B illustrates an extruded web 42″ like the one described above andshown in FIGS. 1B, 2B and 3B traveling in a direction indicated by arrow43.

This method comprises plastically deforming or flattening at leastselected portions or areas 162, 164 of the extruded web 42″ to create aplastically deformed extruded web 166. This plastic deformation mayinclude using movable tools 168, 170 such as shown in FIG. 7B tointerrupt the continuous corrugations or flutes 136 formed in theemerging extruded web 42″ and create a plurality of non-deformed regionsor areas 172 and a plurality of flats or flattened areas 162, 164 eachextending in a second direction perpendicular to the direction of travelof the extruded web, transversely or from side-to-side. The size andlocation of these regions or areas 162, 164 and 172 may vary dependingupon the desired size or shape of the cells 165 of the resultant product160.

Although tool 168 is illustrated as comprising three bars 174 joinedtogether with connectors 176 (only one being shown for clarity) and tool170 is illustrated as comprising two bars 174 joined together withconnectors 180 (only one being shown for clarity), respectively, thesetools 168, 170 may comprise any number of bars of any desired size orconfiguration joined together or not. Although two tools areillustrated, any number of tools of any desired type or configurationmay be used. Again, the term tool is not intended to be limiting and mayinclude any tool known in the art.

During the step of plastically deforming at least selected portions ofthe extruded web 42″, the bars 174 of the tools 168, 170 may be chilled,at ambient temperature, or heated by any desired method to facilitateprocessing. Such heating is illustrated schematically by arrows 178.This heating step is optional and may be used in certain applicationsonly. In other applications it may be omitted partially or entirely.Although it is shown schematically after the flats 162, 164 have beencreated in the extruded web 42″, this heating step may occur any timeduring this manufacturing process.

As best illustrated in FIGS. 7B and 8B, each generally rectangular,transversely extending flat or flattened area 162 is located in theplane P8 of the extruded web 42″. Each generally rectangular,transversely extending flat or flattened area 164 is located in plane P7above the plane P8 of the extruded web 42″. Flattened areas 162 and 164alternate between corrugated or non-deformed regions 172. Eachcorrugated region 172 comprises rows of corrugations.

As shown in FIG. 5B, the plastically deformed web portion 166 is thenfolded along transversely extending fold lines 154 located generally inthe planes P7 and P8 of the extrudate 42″. See FIG. 3B. Such fold lines154 may be optionally scored or perforated at any step in themanufacturing process with cuts (not shown) to assist folding. Suchscoring may be made by a separate tool or tools. As shown in FIG. 6B,after the plastically deformed web portion 166 is folded alongtransversely extending fold lines 154, horizontal walls 130 of extrudate42″ become vertically orientated and the flutes 136 become the cells 14″of the resultant product 160.

FIG. 8B shows a portion of the resultant product 160 along with skins orlayers 80 (shown in phantom) one or both of which may be secured to atleast one of the upper and lower surfaces of product 160 to create amulti-layered or sandwich-like product for any desired use. As shown inFIG. 8B, the plastically deformed web 166 is folded alternatively inupper and lower planes P7 and P8 to create a plurality of blocks 161,each block 161 containing a row of vertically oriented cells like theones shown in FIG. 6B. If desired, adjacent blocks 161 may be adhesivelyor otherwise joined to each other to create product 160 with or withoutskins 80.

Another step in the process may be to cut the extruded web 166 at anydesired location. FIG. 7B illustrates a cutter 78 at one location.However, one or more cutting tools or devices may be used at any desiredlocation to create a product 160 of a desired length.

FIG. 1C depicts an extruder 40 c with an alternate extruder head 41 cused to extrude an extrusion having a non-planar profile and non-linearcross-section as shown in FIGS. 2C and 3C. FIG. 2C depicts a portion ofthe extruded web 42 c formed by use of extruder head 41 c, the extrudedweb 42 c having a non-linear cross-section. FIG. 2C depicts an alternateextruded web 42 c formed by use of extruder head 41 c, the extruded web42 c having a non-linear cross-section. As seen in FIG. 3C, the extrudedweb 42 c has spaced upper and lower horizontal walls 182 in planes P9and P10, the linear distance between these planes defining the height H3of the extrudate 42 c. The extrudate 42 c also has side edges 184, thedistance between which defines the width or transverse dimension W3 ofthe extrudate 42 c. Lastly, the extrudate 42 c has a sinuous middlemember 186 extending between the horizontal walls 182 so as to define aplurality of flutes or channels 188 which extend longitudinally. As seenin FIG. 2C, the extruded web 42 c travels in a direction indicated byarrow 43. The extruded web 42 c may be any desired material of anydesired thickness and/or width. Such an extruded web 42 c may be treatedor processed as described above to create a product for use alone or ina sandwich-like core product.

While we have described several preferred embodiments of the presentinvention, persons skilled in the art will appreciate changes andmodifications which may be made without departing from the spirit of theinvention. For example, although one configuration of a cell isillustrated and described, the cells of the present invention may beother configurations, such as cylindrical in shape. Therefore, we intendto be limited only by the scope of the following claims and equivalentsthereof.

1. A process of making a product comprising: extruding a web of materialhaving a generally non-planar profile; flattening selected areas of theextruded web; and folding the web.
 2. The process of claim 1 furthercomprising forming a plurality of openings in the extruded web.
 3. Theprocess of claim 2 wherein forming a plurality of openings in theextruded web comprises stamping the material.
 4. The process of claim 1wherein flattening selected areas of the extruded web comprisescontacting the extruded web with a heated element.
 5. The process ofclaim 1 further wherein the extruded web has a generally corrugatedshape with flattened peaks and flattened valleys.
 6. The process ofclaim 1 wherein the extruded web is folded along transversely extendingfold lines.
 7. A process of making a product comprising: extruding a webof material such that the extruded web has a generally non-linearcross-section; flattening selected areas of the extruded web; andfolding the extruded web along transversely extending fold lines.
 8. Theprocess of claim 7 further comprising forming at least one opening inthe extruded web.
 9. The process of claim 8 wherein forming a pluralityof openings in the extruded web comprises stamping the material.
 10. Theprocess of claim 7 wherein the extruded web is flattened in selectedareas by at least one tool applying pressure.
 11. The process of claim 7wherein the extruded web is flattened in selected areas by at least onetool applying heat.
 12. The process of claim 8 wherein creating aplurality of openings in the extruded web comprises removing materialfrom the extruded web using at least one tool.
 13. A process of making aproduct comprising: extruding a web of material such that the extrudedweb has a generally non-linear cross-section; plastically deformingselected areas of the extruded web; and folding the extruded web alongtransversely extending fold lines.
 14. The process of claim 13 whereinsaid extruded web is corrugated plastic.
 15. The process of claim 13wherein said step of plastically deforming selected areas of theextruded web comprising using at least one heated tool.
 16. A honeycombproduct comprising: an extruded web having a non-planar profile formedand folded into a plurality of similar cells arranged in rows, at leastsome of the rows of cells being made of two row walls, each of said rowwalls having alternating planar and non-planar regions, the planarregions of adjacent said row walls being joined together and thenon-planar regions of adjacent said row walls defining side walls of thecells, each of the cells having a top and bottom.
 17. The honeycombproduct of claim 16 wherein at least some of the cells have at least oneopening created by at least one tool.
 18. The honeycomb product of claim16 wherein at least some of the openings are in lateral sidewalls of atleast some of the cells.
 19. The honeycomb product of claim 16 whereinat least some of the cells have at least one opening of a predefinedsize.
 20. The honeycomb product of claim 16 wherein at least some of thecells have at least one opening of a predefined shape.
 21. A productcomprising: an extruded web material having a longitudinal dimensionformed into a plurality of similar cells arranged in rows, at least someof the cells being made of a continuous cell wall, the continuous cellwall being in the shape of a ring, the cells oriented substantially 90°to the longitudinal dimension.
 22. A product made by the process of:extruding a web of material, the extruded web having a generallynon-linear cross-section; creating a plurality of generally planar areasin said extruded web; folding said extruded web along edges of saidgenerally planar areas to create a plurality of cells arranged in rows,at least some of the rows of cells being made of two row walls, each ofsaid row walls having planar and non-planar regions, the regions ofadjacent said row walls being joined together, and the non-planarregions of adjacent said row walls defining side walls of the cells,each of the cells having a top and bottom.
 23. The product of claim 22wherein at least some of said tops and bottoms of said cells are in theshape of a polygon.
 24. The product of claim 22 wherein at least some ofthe cells has an opening allowing access to an interior of the cell. 25.The product of claim 22 wherein the polygon is a hexagon.
 26. Theproduct of claim 22 wherein the web of material has a plurality ofopenings formed therethrough.
 27. The product of claim 22 wherein thefolding of said extruded web creates a plurality of identical cellsoriented 90° relative to said extruded web.
 28. The product of claim 25wherein at least some of the openings are located in the tops andbottoms of the cells.
 29. The product of claim 22 wherein the materialis plastic.
 30. A product made by the process of: extruding a web ofmaterial, the extruded web having a generally non-linear cross-section;creating a plurality of generally planar areas in said extruded web;folding said extruded web along edges of said generally planar areas tocreate a plurality of cells arranged in rows.
 31. The product of claim30 wherein the extruded web is corrugated plastic.
 32. A product made bythe process of: extruding a web of material, the extruded web having agenerally non-linear cross-section; creating a plurality of plasticallydeformed areas in said extruded web; folding said extruded web alongsaid plastically deformed areas to create a plurality of cells arrangedin rows.
 33. The product of claim 32 wherein the extruded web iscorrugated plastic.
 34. The product of claim 32 wherein the cells arevertically oriented.